On the p-divisibility of Fermat quotients. - Reijo Ernvall; Tauno Metsänkylä (Math. Comput., 1997)

Irregular Primes and Cyclotomic Invariants to 12 Million. - Joe Buhler; Richard E. Crandall; Reijo Ernvall; Tauno Metsänkylä; Mohammad Amin Shokrollahi (J. Symb. Comput., 2001)